Printing plate clamping mechanism



Dec. 3, 1 935. F. e. LOUGEE ET'AL 2,022,681

PRINTING PLATE CLAMPING MECHANISM I Filed March 17, 1953 4 Sheets-Sheet1 lawfatwv 1935- F. ca. LOUGEE- ET AL PRINTING PLATE CLAMPING MECHANISMFiled March 17, 1933 4 Sheets-Sheet 2 4Sheets-Sheet 3 F. G. LOUGEE ET ALFiled March 17, 1933 E 3 w Y w W\ PRINTING PLATE CLAMPING MECHANISM L An E E G U 0 L G F PRINTING PLATE CLAMPING MECHANISM 4 Sheets- Sheet 4Filed March 17, 1933 INYENTOR$ wa Patented Dec. 3, 1935 UNITED STATESPATENT OFFICE PRINTING PLATE CLAMPING MECHANISM Frederick GraftonLougee, New Malden, and Thomas Edward Pattinson, Finchley, London,England, assignors to Irving Trust Company, permanent trustee for R. Hoe& 00., Inc., New York, N. Y., a corporation of New York ApplicationMarch 17, 1933, Serial No. 661,318 In Great Britain May 24, 1932 24Claims. (01. 101-378) This invention relates to improvements in meansfor clamping printing plates, fudge boxes and the like, and is animprovement over the mechanism shown in our application Serial No.622,446 filed July 1a, 1932 for Improvements in printing plate clampingmechanism.

One object of the present invention is to provide an arrangement whichwill enable a considerable economy to be effected in the time requiredfor clamping and unclamping printing plates, fudge boxes and the like.

A further object of the present invention is to provide an arrangementwhich will insure that the plates will always be tightly clamped despitewear which may take place during a run of the printing machine.

It is also an object of the invention to provide a plate clampingmechanism of generally improved construction, whereby the device will besimple, durable and inexpensive in construction, as well as convenient,practical, serviceable and efficient in its use.

With the foregoing and other objectsin view, which will appear as thedescription proceeds, the invention resides in the combination andarrangement of parts, and in the details of construction hereinafterdescribed and claimed.

, According to the present invention a clamping member for a printingplate, fudge box or the like is adapted to be actuated by power undermanual control, the power medium preferably being a fluid, convenientlyair, under pressure.

Means are provided for automatically retaining or looking the clampingmember in clamping position in the event of failure of the fluidpressure.

The invention will be best understood by referring to the accompanyingdrawings in which:

Figure 1 is a fragmentary longitudinal sectional view of a printingcylinder showing one of the valve means, certain of the fluid-conductingpassages and one of the pistons employed for lockingly securing aprinting plate tothe cylinder, other means being disclosed which mayoptionally be employed in order to accommodate the printing plateclamping members to operatively engage plates of various sizes; the viewbeingtaken on the line l--l of Figure 2 and in the direction of thearrows;

Figure 2 is an end elevational view, with certain parts removed for thepurpose of clearer illustration, of the arrangement shown in Figure 1;

Figure 3 is a fragmentary transverse sectional view of a pawl andratchet arrangem nt; for

taining one of the end clamp locking segments in desired position;

Figure 4 is a fragmentary transverse sectional View showing thedisposition of the piston receiving chambers, plate-clamp lockingmembers, 5 and certain other coasting details of construction;

Figure 5 is a fragmentary sectional view of a modified form of means foradjusting the plate clamps to engage printing plates of various sizes;

Figure 6 is an end elevational view of a printing cylinder with certainparts removed for clearer illustration wherein a modified form of plateclamping means is employed;

Figure '7 is a fragmentary plan elevational view partly in section ofdetails shown in Figure 6;

Figure 8 is a fragmentary elevational view showing certain other detailsof the modified construction shown in Figure 6;

Figure 9 is a fragmentary sectional detail view showing the arrangementof passages in the plug cock or valve and the ducts and passages in thecylinder coacting therewith, the valve being in position to admit air tothe right hand end of the piston chamber and to exhaust air from theleft hand end; and

Figure 10 is a view similar to Figure 9 showing the valve in position toreverse the functions mentioned as to Figure 9.

A preferred form of the invention is illustrated in Figures 1 to 4inclusive and 9 and 10 of the accompanying drawings, and modified formsof construction are illustrated in Figures 5 to 8.

. Referring firstly to Figures 1 to 4 and 9 and 10, these figuresillustrate an arrangement for use with a printing cylinder l of anewspaper press which carries two plates around and four plates alongthe cylinder and is provided with the usual fixed central abutment,intermediate floating dogs or clips and end clamps 2. The cylinder isprovided at each end with four borings 3 which forms cylinders forpistons 4, the outermost ends of the bearings being sealed by coverplates 5 secured to the printing cylinder.

The printing cylinder is slotted to enable the end clamp blocks 2' whichslide on guides 6 secured to the cylinder, to be connected each to oneof a pair of the pistons which are grouped in two pairs of two. Theopposite ends of the cylinders are open to passages I, 8, the passages 1of each pair of cylinders branching from a common chamber 9,'and thepassages 8 branching from a common chamber 10. The chambers 9 and It!can be placed in communication alternately with a common pressure airsupply passage H and with i exhaust passages l2, provided in thecylinder 5 by cocks I3.

As illustrated in Figure 1, it is to be understood that the cock l3, thefluid-conducting passages and other coacting details are operativelyassociated with the pair of piston-receiving chambers 3 shown at thelower portion of the cylinder l in Figure2; and that the upper pair ofthese piston-receiving chambers 3, one of which is shown in the upperportion of Figure l is connected to the supply of fluid pressure bysimilar details not shown in Figure 1.

Each cock l3 has atransverse passageway [3 which, by turning of the cook53, to the position shown in Figures 1 and 9, may be aligned with a pairof radially extending ducts l formed the cylinder 1 and arrangedperpendicularly to the fluid supply passage 6 i with which theycommunicate. Each of the plug cocks l3, as best shown in Figures 9 and10, is formed with two peripheral, longitudinally-extending grooves, anda central bore 16 which communicates with two ports I1, 11', formed inthe cock, the port I! being adapted to put the bore l6 intocommunication with one of the exhaust passages l2 when the cook 53 isturned to the position shown in'Figure 9 in order to exhaust the lefthand end of the chambers 3 while fluid under pressure is entering intothe right hand end via supply passage l l, duct M, transverse passagewayl3, chamber 9 and passages l. The

. port ll opens into the groove is and serves when the cock I3 is turnedto the position shown in Figure 10 to put the bore it into communicationwith the groove i 5 and hence with duct M, there- 'by admitting air orother fluid under pressure to the left hand end of the chamber 3 whilethe right hand end is being exhausted via the chamber 9, the lowerportion of duct i i, groove l5 and the L-shaped exhaust passageway l2.

Thus, the cock when placing the chamber 9 communicating by the passage'1 with the end of the grouped cylinders, into communication with thepressure air supply passage II via the bore 14, places the chamber l0communicating by passage 8 with the other ends, into com.- municationwith the exhaust passage l2 and vice versa, when the cock i3 is turnedto apply fiuid pressure to the rear of the cylinders 3.

Thus, when it is desired to move one or other of the end clamps 2 intoor out of clamping position, the correspondingvcock is turned, wherebythat side of the grouped pistons which was subjected to the pressure ofthe air is opened to exhaust and the other side becomes subjected to thepressure of the air, thereby compelling the pistons 4 to move, and thusto move the clamp. It will be apparent that this operation can beeffected easily and quickly, thereby efiecting a considerable saving inthe time required for changing plates.

It will also be apparent that as the pistons are constantly subjected toair pressure, the clamps are constantly urged into engagement with theplates (indicated at it) on the printing cylinder, and would follow-upany wear or flow of the metal of which the plates are formed which mightoccur, and thus there would be no danger that the plates would becomeloose.

In order to insure that the end clamps shall be maintained in clampingposition should a breakdown in the air supply occur, means are providedfor positively locking the clamps. In the arrangement shown in Figures 1to 4, 9 and 10, this is effected by providing end extensions orprojecting bars is for each of the clamp blocks 2' and a locking segment20, one for each of the extensions on each block 2, the segments 20forming abutments for the corresponding extensions l9 when the clampconnected thereto is in clamping position. The segments 20 are formedwith apertures 2| which can be moved, by rocking the segments into linewith the extensions I9 to permit these latter and hence thecorresponding clamps to move out of clamping position. Inasmuch as theremay occur slight variations in the length'of a printing plate, theabutting or looking portion of the segments 26 is formed with a taperingsurface so that the segment can be rocked until the correspondingextensions l9 are engaged by one part or the other of the taperedsurface. The segments are each normally prevented from reversing to moveout of locking positions by pawls 22 pivotally mounted at 23 on thecylinder and the teeth of which are arranged to engage teeth 24 formedon the inner periphery of the segments, the pawls being urged intoretaining position by sprng loaded plungers 25. Three pawls are providedfor each segment, the teeth on the pawls being staggered so as toprovide a small movement of the segment from one looking position to thenext. Thus, as the segments are moved into retaining position, the teethon the segments click past those on the pawlswhich however, prevent theunintentional reverse movement of the segments. To eifect reversemovement of the segments, there are provided in the segments, apertures26 for the reception of tools arranged to depress the pawls.

In the arrangement illustrated, the movement of the segments into andout of retaining position is arranged to effect simultaneous movement ofthe corresponding cocks. This is effected by pro viding the segmentswith pins 21 arranged to engage the limbs of forked arms 28 secured tothe cocks, one limb of each forked arm being longer than the other. Theinitial movement of the segments towards retaining position is employedsolely to actuate the corresponding cock to allow air to be admitted tothe right hand ends of the corresponding grouped pair of pistons, theapertures 2| in the segments being lengthened to permit the clearing ofthe corresponding extensions l9 durin this initial movement. Themovement of the segment is con inued until the tapered surface abutsagainst the corresponding projections, the cocks being prevented fromreversing by engagement between the pins 21 and the short limbs of thearms 28'. During the reverse movement of the segments, the taperedsurfaces thereon are caused to move clear of the' correspondingextensions !9 and the pins 2! move against the long limbs of the arms 23so that the corresponding cock is reversed to admit air to the left handends of the corresponding grouped cylinders, the apertures 2| movinginto line with the extensions I9 to allow movement thereof. It will beseen that the pawls 22 not only serve to retain the segments in lockingposition but also act to prevent movement of the corresponding cock.

While the arrangement employing the tapered surfaces is preferred, themodification illustrated in Figure 5 may be employed. In thisarrangement, the extensions are threaded adjustable studs 29 arranged toabut against plane surfaces formed on segments 33 and contained inplanes atright angles to the axis of the cylinder, the studs beingadjusted, when the clamps have been moved to clamping formed by screwposition until they abut against the said plane surfaces.

The segments 20 or 30 may as shown in Figures 6 to 8 be replaced byrings 3 I, 32 one for each end clamp, which figures also illustrate anarrangement in which adjustment to accommodate plates of slightlydifferent size is dispensed with, although this feature of adustment ispreferred and may take the form shown in Figures 1 to 4, 9 and 10 orFigure 5. In the instant arrangement, the inner ring 32 is provided withtwo sets 33, 34 of apertures, those of one set 34 being those which canbe moved by movement of the ring 32 into and out of line with theextensions IS on the one end clamp and those of the other set beingmerely clearance apertures to enable the extensions IS on the otherclamp to extend through and into cooperation with its own retaining ring3|, which latter is provided with only one set of apertures 35 forcooperation with its extensions. In this modification also, a slightlymodified form of locking arrangement for the rings and interconnectionof the rings with the corresponding cock is provided. The rings 3|, 32are provided with recesses 36 to receive an operating tool and arecounter-bored to receive either of a pair of spring loaded locking pins31, 38 in positions corresponding to the locked and unlocked positionsof the rings. In order to prevent withdrawal or insertion of theoperating tool at any position except the fully locked and unlockedposition there are provided fixed plates 39 which are shaped at theirends to form a continuation of the recesses 36 and between their endsare shaped to cooperate with the tool to prevent withdrawal thereof. Therings are cut away as indicated at 40 to receive rollers 4! formed onarms 52 secured to the respective cocks so that as the rings are moved,the corresponding cocks are simultaneously moved.

Referring again to Figures 1 to 4, 9 and 10, these figures alsoillustrate an arrangement by means of which the end clamps can beadjusted to clamp plates which differ widely in width, e. g., a sevenand an eight column plate. In the arrangement shown, the blocks 2 areformed with internal mutilated shoulders 50 which are normally connectedto the corresponding pistons through mutilated shoulders formed on theextensions is, which latter are rotatable but not movable axially inbrackets 52 secured to the pistons 4, the extensions I9 being formedwith a head 53 arranged to receive a tommy pin. By partially rotatingthe extensions I9, the gaps formed by the mutilation of the shoulders 5|thereon can be moved into line with the multilated shoulders on the endclamp which can then be moved freely in an axial direction to thedesired position whereafter connection is re-established between theextensions I9 and the clamps 2 by rotating the extensions to theiroriginal posi-- tion. A set screw 54 or other locking device is providedto lock the extensions in the position in which they connect the endclamps to the corresponding pistons.

In order to allow the pistons to move in the clamping or both theclamping and unclamping direction without being subjected to a dampingeffect due to the exhaust of air, any convenient device may be providedfor allowing air to be exhausted, from one side of the pistons whenpressure is applied to the other side, at a rate greater than that atwhich pressure is supplied to that side. This may be convenientlyeifected by providing an additional exhausting passage or passages whichcan be opened by a valve or valves when the pistons are supplied withair under pressure at the opposite side, the valve or valvesconveniently being actuated by the initial movement of the pistons.

In order to allow the cylinder to be plated-up with the central platesonly, each piston may be provided with a rod which engages an abutmenton the floating dog to move this latter directly into clamping position(i. e., without the intervention of the other plates along the cylinder)the length of the rod and the location of the abutment being such thatthe rod does not move into contact with the abutment within the range ofmovement of the pistons when all the plates along the cylinder areemployed.

The supply of air under pressure to the passages in the shaft iseffected through any convenient form of rotary coupling such as thatindicated at 66 in Figure 1.

In order to conserve the air acting on the pistons should a breakdownoccur in the pressure air supply, there is provided a valve 61 whichautomatically closes when the pressure on the supply side drops, andthereby prevents the return to the supply of the ,air acting on thepistons. Also an automatic cut-out can be conveniently attached to shutdown the motors and stop the press, if there is any failure of airpressure. This cut-out can be so arranged as to act at any desiredsafety margin of pressure. The common supply passage may also beprovided with a cock which can be opened when it is desired to move theclamps to allow the escape of the air retained by the automatic valve.

If desired, manual clamp operating means may additionally be providedfor use in the event of a prolonged breakdown in the pressure airsupply.

The invention may obviously be applied to any arrangement of printingplates and any number thereof on a printing cylinder. and is obviouslyapplicable to the actuation of the clamps for clamping fudgeboxes inposition.

It will be understood that the invention may be embodied in otherspecific forms without departing from the spirit or essentialattributes) thereof, and it is therefore desired that the presentembodiment be considered in all respects as illustrative and notrestrictive, reference being had to the appended claims rather than tothe foregoing description to indicate the scope of the invention.

What we claim is:

1. In a device of the character described, the

combination of a printing cylinder, a plurality of chambers formed insaid cylinder, said chambers having pistons attached to printing plateclamping means, fluid conducting means communicating With the chambersfor admitting and exhausting fluid to actuate said pistons andconsequently said plate clamping means, valve means for opening andclosing said fluid conducting means, and manually operable means foractuating said valve means and preventing the accidental disengagementof said plate clamping means from a plate secured on said cylinderthereby.

2. In a device of the character described, the combination of a printingcylinder, a plurality of chambers formed in said cylinder, said chambershaving pistons attached to printing plate clamping means, fluidconducting means for admitting and exhausting fluid to actuate saidpistons and consequently said plate clamping means, valve means foropening and closing said fluid conducting means, and means slidablymounted on said and exhausting fluid to actuate said pistons andconsequently said plate clamping means, valve means for opening andclosing said fluid conducting means, and manually operable meansadiustably and slidably mounted on said cylinder for turning said valvemeans and for simultaneously interposing mechanical means preventingaccidental operation of the first mentioned means and detachment of aprinting plate secured to the cylinder by same.

4. In a device of the character described, the combination of a printingcylinder formed with fluid conducting means communicating with chambersarranged in said cylinder, said chambers accommodating pistons slidablymounted therein, said pistons having plate clamping means fastenedthereto, valve means for opening andclosing said fluid. conductingmeans, and manually operable means mounted on the periphery of saidcylinder for operating said valve means and Wedgingly maintaining saidplate clamping means in position to confine a printing plate on theperiphery of the cylinder in case of failure of fluid pressure.

5. In a device of the character described, a cylinder having a chamber,fluid inlet and exhaust passages arranged in said cylinder andcommunicating with said chamber, a piston reciprocatingly mounted insaid chamber, .a plate engaging clamp fastened to said piston, andannular means mounted on the periphery of the cylinder for actuatingvalve means adapted to open and close said inlet and exhaust passages,said annular means also serving to prevent said clamp from beingdisengaged with a printing plate arranged on the cylinder in case ofaccidental failure of fluid pressure.

6. In a device of the character described, .a printing cylinder, achamber secured in said cylinder, a piston reciprocatingly mounted insaid cylinder, a valve secured in said cylinder and adapted to open andclose fluid conducting passageways arranged in the cylinder, saidpassageways communicating with a source of fluid pressure and saidchamber, a plate clamping element secured to the piston, and a manuallyoperable member arranged on the cylinder for actuating the valve; saidmanually operable member being adjustably held in any selected positionby a pawl secured to the cylinder.

7. In a device of the character described, the combination of asubstantially solid metal cylinder provided with fluid conductingpassageways and recessed to provide chambers having pistons therein,said pistons being secured to plate engaging clamps, valves operablyarranged in the said cylinder for opening and closing said passagewaysto admit fluid into the chambers and exhausting said fluid therefrom,and manually operable means for actuating said valves and for preventingthe disengagement of said clamps with printing plates securable onthe-cylinder, said means consisting of a plate arranged on said cylinderand lockable by stops also arranged on the cylinder.

8. In a device of the character described, the

combination of a piston reciprocatingly mounted in a cylinder, manuallyoperable means for s controlling a supply of fluid under pressure to thesaid piston whereby the latter can be caused to move backward andforward, a printing plate clamping member connected to said piston andmovable thereby into and out of clamping position, and other meansmovable into and out of the path of the clamping member for retainingthe latter in a selected position and optionally freeing same fromrestraint, said last mentioned means being adapted to move with themanually operable means.

9. An arrangement as set forth in claim 8 in which the plate clampingmember includes an element, said element having apertures, whereby whenthe element is moved the apertures can be moved into and out of linewith the clamping members.

10. The arrangement set forth in claim 5 in which the annular means hasan inclined retaining surface.

' 11. An arrangement as set forth. in claim 8 wherein an adjustablemember is interposed between the clamping member and the last mentionedmeans.

12. An arrangement as set forth'in claim 8 wherein the clamping memberis disconnectible from the piston inorder to adjust the said clampingmember.

13. An arrangement as set forth in claim 8 wherein a connector isinterposed between the clamping member and the piston, said connectorhaving mutilated shoulders engageable with teeth formed on the clampingmember, the connector being rotatable to move the mutilations into andout of line with the teeth.

14. An arrangement as set forth in claim 8 wherein the plate clampingmember comprises an element apertured to receive a tommy pin foradjusting the said clamping member to engage printing plates of varioussizes and retain same operatively on the said cylinder.

15. In a device of the character described, the combination of aprinting cylinder having chambers, pistons slidably mounted in saidchambers, plate clamping members fastened to said pistons, and meansincluding tool-operated members for securing said clamping members indesired positions for retaining and releasing printing plates on saidcylinder; said means including a pawl secured to the cylinder andcoactable with an element wedgingly engageable with the plate clampingmembers.

16. In a device of the character described, a substantially solidcylinder recessed to provide chambers and fluid conducting passagescommunicating therewith, pistons arranged in said chambers, plateclamping means secured to said pistons, members movably mounted on theperiphery of said cylinder and shiftable into locking engagement withthe clamping means to retain same in position to confine printing platesoperatively on the cylinder and to permit the detachment of the saidprinting plates from the cylinder when desired; said members beingapertured to receive an operating instrumentality and formed with aratchet coactable with a pawl secured to the cylinder.

17. In a device of the character described, the combination of acylinder. having a chamber receiving a piston, said piston having aplate engaging clamp secured th reto, valve means in said cylinder foradmitting fluid pressure into said chamber and exhausting sametherefrom.

and manually operable means connected to said valve means'for actuatingsame, said manually operable means being provided with a ratchet engagedby a pawl secured to the cylinder, whereby said clamp may lockinglyengage printing plates of various sizes on said cylinder and confinesame operatively thereon until release is required.

18. In a device of the character described, the combination of a piston,manually operable means for so controlling a supply of fluid underpressure to the piston that the piston can be caused to move forward andbackward, a printing plate clamping member operatively connected to thepiston and movable thereby, and means including a segment wedginglyengaged with said plate clamping member for maintaining the latter inoperative engagement with a plate on said cylinder independently offluid pressure means, said segment being simultaneously operated withthe said manually operable means.

19. In a device of the character described, the combination of acylinder having a chamber receiving a piston, said piston having a plateengaging clamp secured thereto, valve means in said cylinder foradmitting fluid pressure into said chamber and exhausting sametherefrom, and manually operable means connected to said valve means foractuating same, said manually operable means being rendered operative byapplying a tool thereto for manipulating the valve means, and renderedinoperative to actuate the valve means but automatically effective tolock same in open and closed. positions when said tool is withdrawn fromengagement with the manually operable means.

20. In a device of the character described, the combination of a piston,valve means for so controlling a supply of fluid under pressure to thepiston that the piston can be caused to move forward and backward, aprinting plate clamping member operatively connected to the piston andmovable thereby, and selflocking means wedgingly engageable with saidplate clamping member and mechanically connected to the valve means,whereby the said valve means may be actuated and the plate clampingmember secured against accidental release, said self -locking meansbeing released for actuation upon the application of a tool butautomatically becoming self-locking upon the withdrawal of said tool.

21. In a device of the character described, the combination of acylinder, a piston reciprocatingly mounted in said cylinder, a plateengaging clamp secured to said piston, valve means for controlling asupply of fluid under pressure to the piston for moving same backwardsand forwards, manually operable means movably mounted on said cylinderand mechanically connected to said valve means for actuating same tocontrol the supply of fluid pressure to the piston, said manuallyoperable means being self-locking to secure the plate clamp againstaccidental operation, but released for manipulation when engaged by atool adapted to fit into said manually operable means.

22. An arrangement as specified in claim 8, and means for arranging theplate clamping member to accommodate slight variations in plate widths.

23. An arrangement as specified in claim 8, and means for adjusting theclamping member relatively to the piston.

24. In a form cylinder for a printing machine adapted to receiveprinting plates thereon, a clamp movable to engage a plate, a pistonmovable within the cylinder and connected to the clamp, a locking devicemovable to secure the clamp in locked position, and valve mechanism tocontrol the flow of fluid to the piston for operating the clamp; saidlocking device being movable with the valve mechanism.

FREDERICK GRAFTON LOUGEE. THOMAS EDWARD PATTINSON.

